M9312 DIP settings, very similar on other devices that use these ROMs:

S1	ON=enable page at 765000 (console emulator), OFF=disable
S2	ON=internal boot enable, OFF=external boot (??? 11/44 meaning)
S3-S10	starting offset in ROM at 773000 (S1=OFF) or 765000 (S1=ON)
	S3=bit 8, S10=bit 1, ON=1 OFF=0

Most boot ROMs start at offset 4 (according to Al Sieving), so for example to
auto-boot an RL11, S2=ON, S9=ON, all others=off (how mine was set before I
messed with it).

According to Tony Duell, it's like this:
main device (or unit 0):  +04 (no diag), +06 (with diag)

2nd device on DP:+DB: ROMs:  +50 (no diag), +52 (with diag)

2nd device on DK:+DT: or TT:+PR: ROMs:  +34 (no diag), +36 (with diag)

Unit 1 (for DMC11, DU11, DUP11 ROM):  +30 (no diag), +32 (with diag)

Console emulator starts at 765020, so S1=ON, S2=ON, S7=ON, others=OFF.

To get the CMD SCSI menu:
L 772152
D 123456
L 772152
D 100
L 5000
S